Reasoning over Merged Semantic Graphs across Multiple Frameworks for Fact Verification

The Hong Kong University of Science and Technology
Department of Computer Science and Engineering


MPhil Thesis Defence


Title: "Reasoning over Merged Semantic Graphs across Multiple Frameworks for
Fact Verification"

By

Mr. Ngo Yin WONG


Abstract:

The rapid proliferation of misinformation on the internet has led to an 
increased need for reliable and efficient fact verification systems. In 
this thesis, we propose a novel fact verification system that leverages 
semantic graphs to enhance reasoning in multi-evidence situations. Our 
system performs reasoning by joining semantic graphs of various retrieved 
evidence sentences from a trusted fact corpus. Additionally, our system 
combines semantic graphs from different frameworks to jointly make claim 
verification predictions, providing a more comprehensive understanding of 
the underlying facts. We also incorporate a language model-based retrieval 
model to improve the retrieval of relevant evidence sentences, further 
enhancing the overall performance. Experimental results on the FEVER 
dataset demonstrate that our approach outperforms existing fact 
verification systems, especially in cases where multiple pieces of 
evidence are required for verification. Ablation studies are conducted to 
analyze the contributions of different components within our system. This 
work not only contributes to the advancement of fact verification methods 
but also lays the groundwork for future research in the area of semantic 
graph-based reasoning systems.


Date: 			Tuesday, 6 June 2023

Time: 			4:00pm - 6:00pm

Venue: 			Room 3494
			lifts 25/26

Committee Members: 	Dr. Yangqiu Song (Supervisor)
			Prof. Raymond Wong (Chairperson)
			Dr. Xiaojuan Ma


**** ALL are Welcome ****